Constant hyper::header::FROM

pub const FROM: HeaderName = HeaderName{inner: Repr::Standard(StandardHeader::From),}

Contains an Internet email address for a human user who controls the requesting user agent.

If you are running a robotic user agent (e.g. a crawler), the From header should be sent, so you can be contacted if problems occur on servers, such as if the robot is sending excessive, unwanted, or invalid requests.